Re: May we trust IntegerQ ?
- To: mathgroup at smc.vnet.net
- Subject: [mg107509] Re: [mg107488] May we trust IntegerQ ?
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Mon, 15 Feb 2010 05:47:21 -0500 (EST)
- References: <201002141316.IAA02260@smc.vnet.net>
On 14 Feb 2010, at 14:16, Artur wrote:
> Procedure: find such x that ChebyshevT[x/2, x] isn't integer
> aa = {}; Do[ If[IntegerQ[ChebyshevT[x/2, x]], , AppendTo[aa, x]], {x, 0,
> 20}]; aa
> and answer Mathematica is set:
> {3, 5, 7, 9, 11, 13, 15, 17, 19}
> where occered e.g. number 7
> N[ChebyshevT[7/2, 7],100]
> 5042.00000000000000000000000000000000000000000000000000000000000000000\
> 0000000000000000000000000000000
> evidently is integer 5042
> Some comments ?
>
> Best wishes
> Artur
>
>
>
>
FunctionExpand[ChebyshevT[7/2, 7]]
5042
so it definitely is an integer.
Andrzej Kozlowski
- References:
- May we trust IntegerQ ?
- From: Artur <grafix@csl.pl>
- May we trust IntegerQ ?